tam-sam-som-calculator — Claude Code skill: market sizing
Takes a product idea through TAM, SAM and SOM with adaptive questions, assumptions written down, and a bottom-up estimate you can source. Built for business cases.
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a claude-codeWhat tam-sam-som-calculator does
The skill moves a product manager through three tiers of market: everything out there, what the company can reach, and what it can actually win. Each turn offers numbered choices, and the next question changes depending on your answer. It stops at four questions.
There are three ways in. Bring your own population and ARPU numbers and go straight to the arithmetic. Sit through a guided interview that builds the inputs with you. Or hand the agent research mode, where it assembles a bottom-up figure from government statistics and filings while you audit the sources. A helper script handles the math deterministically and returns a Markdown table; template.md holds the full fill-in structure.
The script fetches nothing by itself, so with no population and ARPU figures in hand the arithmetic step has nothing to work on. A session is estimated at 20-40 minutes. Internal tools with a captive audience are a poor fit, since there is no outside market to size.
What it helps with
- size a market for a product idea
- defend the number in front of a CFO
- replace a slide figure with a bottom-up estimate
- document assumptions so others can attack them
- check whether the market is big enough for a business case
Example prompts for the agent
tam-sam-som-calculatordispatch software for field crews in DACH; I have no numbers, research it yourself- Break down a B2B service for mid-size freight carriers in Europe into TAM, SAM and SOM
How to install tam-sam-som-calculator
1Skills CLI (Vercel)
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a claude-code2Manually: put the files in place
~/.claude/skills/tam-sam-som-calculator/SKILL.mdCopy the whole skill folder; for one project use .claude/skills/tam-sam-som-calculator/
1Skills CLI (Vercel)
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a codex2Manually: put the files in place
.agents/skills/tam-sam-som-calculator/SKILL.mdFor all projects use ~/.agents/skills/
1Skills CLI (Vercel)
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a cursor2Manually: put the files in place
.cursor/skills/tam-sam-som-calculator/SKILL.mdCursor also reads .agents/skills/ and .claude/skills/
1GitHub CLI
gh skill install deanpeters/Product-Manager-Skills tam-sam-som-calculator2Manually: put the files in place
.github/skills/tam-sam-som-calculator/SKILL.md1Skills CLI (Vercel)
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a gemini-cli2Platform CLI
gemini skills install https://github.com/deanpeters/Product-Manager-Skills --path skills/tam-sam-som-calculatorManually: put the files in place
.devin/skills/tam-sam-som-calculator/SKILL.mdThe legacy .windsurf/skills/ path still works
Skills CLI (Vercel)
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a opencodeClaude.ai
Zip the folder and upload it in Settings → Capabilities → Skills
Step by step, with commands for each platform: How to install skills in Claude Code: five ways
Questions about tam-sam-som-calculator
How do I install tam-sam-som-calculator in Claude Code?
Run npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a claude-code. The skill file lands at ~/.claude/skills/tam-sam-som-calculator/SKILL.md.
What does tam-sam-som-calculator do?
It sizes three market layers for an idea: the whole market, the part a company can serve, and the share it can take in the next 1-3 years. Method and assumptions stay visible, which makes the number defensible.
What do I need before the arithmetic step works?
Population and ARPU figures. Without them the helper script has nothing to compute, so take the guided interview route and let the agent build the inputs first.
